1. Field of the Invention
The claimed invention relates to image processing systems in general, and to stereo vision processing systems, apparatus, and methods in particular.
2. Description of the Related Art
The field of stereo vision has received a great deal of attention over the past decade. New algorithms have been developed, and existing algorithms have been augmented and tuned in efforts to both produce more accurate results and obtain them faster. The nature of the stereo vision problem makes these two endeavors non-trivial. The accuracy of results is affected by missing information such as that caused by occlusions, slanted surfaces, and other issues relating to extracting information about three dimensions from two dimensional images. The number of pixels that each image contains increases the number of calculations required to match it with any number of possible matches, making the correspondence problem a computationally complex one that severely limits the speed at which one can obtain results.
Most of the time, accuracy and speed are pitted against each other, making it more difficult to obtain more of both at the same time. Although much of the academic literature does not address the tradeoff between accuracy and speed, many stereo vision applications are sensitive to that tradeoff.
In most circumstances, determining an acceptable tradeoff between speed and accuracy is dependent upon the target application. Although many applications have existed for some time, more and more applications are being developed that could benefit from real-time three-dimensional information. Image sensors and processing hardware are becoming more prevalent, especially because they are available as light-weight, low-power, passive devices. Basic low-quality image sensors can be found on systems from cell phones to entertainment game consoles to security systems to high-tech micro unmanned aerial vehicles. Each of these systems may have limited computational resources for several possible reasons, including constraints on weight, size, power, and cost, or perhaps a requirement that the bulk of computing resources be dedicated to a different primary task.
Accordingly, what is needed is apparatus and methods for stereo vision that provide high levels of speed and accuracy, and can be deployed in resource-limited systems.